In handheld working tools comprising antivibration elements, there is often a compromise between a low amount of vibrations in the handle grip and good manageability. In chain saws, a handle part of the saw is isolated from vibrations in a motor part through a plurality of spring elements attached between the two parts. To do this effectively, the springs are made as soft as possible. However, with soft springs the manageability during operation is degraded and the chain saw becomes difficult to accurately work with.
One way of improving the vibration isolation effect is presented in U.S. Pat. No. 6,994,068. It discloses an antivibration device in a handheld working tool with an antivibration element mounted between a motor unit and a vibration-insulated unit. The antivibration element comprises a spring element attached to one of the two units, and an element of foamed elastic material having a plurality of radially projecting ribs in contact with the other of the two units. The elastic material element provides improved stabilization when active, but at the same time are the vibrations in the vibration-insulated unit increased. The vibrations in the vibration-insulated unit may be decreased by the spring element when the elastic material element is not active. This solution only slightly improves the manageability, and that is at the sacrifice of the vibration isolation.
It is wishful to provide a working tool with antivibration elements that both effectively isolates vibrations between the two parts of the working tool, and improves the manageability during operation.